This invention relates to an apparatus and a method for mounting a fuel supply device in an internal-combustion engine, in particular for a motorcycle.
In the case of internal-combustion engines, it is known to fasten the fuel distributor directly to the cylinder head of the engine. The fuel distributor is preferably mounted relatively closely to the engine to conserve space and to reduce the distance that fuel must travel inside the engine. Unfortunately, mounting the fuel distributor on the cylinder head subjects the fuel distributor to substantial engine vibration and to high temperatures during operation. As a result, there is a risk that the fasteners or the entire fuel supply device will be damaged. Also, thermal expansion may cause the fuel supply device to unfasten itself from the engine or may damage the fasteners which hold the fuel supply device on the engine.
A need therefore exists for a fastening apparatus and a method of fastening a fuel supply device to an internal-combustion engine which reduces the vibration transmitted to the fuel supply device, is resistant to damage caused by engine heat, is arranged in a space saving manner, can adapt to accommodate thermal expansion, and provides a relatively short path between the fuel supply device and the rest of the engine.
The present invention provides an improved air intake connection capable of supporting a fuel supply device on a motorcycle engine. Preferably, the motorcycle engine includes two cylinders in a V-shaped configuration. In alternative embodiments of the present invention, the engine can have any number of cylinders, including one, two, three, or four. Similarly, the engine can have a V-shaped configuration or can have an in-line or a straight configuration. In embodiments with more than one cylinder, it may be desirable to mount the fuel supply device between two air intake ports. Alternatively, given the particular configuration of the engine, it may be desirable to mount the fuel supply device to a single cylinder. Similarly, the configuration of the particular engine may make it more desirable to mount the fuel supply device to three, four, or more air intake ports.
In a first aspect of the present invention, a fuel supply device is mounted to two air intake connections. The air intake connections each have a body portion, a flange extending radially from the body portion, and a projection that extends radially from the body portion. The body portion is made of a relatively resilient material and the flange is made of a relatively non-resilient material. Preferably, the flange is aluminum and the body portion is rubber. The air intake connection is preferably mounted to the engine with one or more fasteners inserted through the flange.
For mounting the fuel supply device to the air intake connections, each projection includes an aperture extending therethrough. An annular recess extends around the inside wall of each of the aperture. A sleeve with an annular protrusion extending radially around the sleeve is preferably inserted into the aperture. The annular recess is adapted to receive the annular protrusion in positive locking engagement. In this manner, the sleeve is coupled to the projection and can rotate inside the aperture in the protrusion but cannot slide out of the aperture. Therefore, the sleeve remains in positive locking engagement with the protrusion when the sleeve rotates relative to the aperture in the protrusion. A fastener is inserted through a fastening lug in the fuel supply device and into the sleeve to secure the fuel supply device to the air intake connection. In this manner, the fastener can be tightened to hold the fuel supply device to the air intake connection. In the event that the fastener is excessively torqued during tightening, the sleeve can spin in the aperture without damaging the projection or the aperture in the projection.
Additionally, because the flanges are preferably made of a relatively resilient material, a change in distance between the two air intake connections caused by thermal expansion does not damage the apertures in the protrusions. Preferably, the metal fasteners rotate inside the apertures to accommodate thermal expansion in the engine, which can include the cylinder heads moving toward each other, moving away from each other, or rotating with respect to each other. Further advantageous embodiments and improvements of the apparatus and method for mounting a fuel supply device in an internal-combustion engine according to the invention are described below.